This article aims to investigate the diet and seed dispersion of the crab-eaten fox, Cer- docyon thous (Linnaeus, 1766), in the Restinga de Jurubatiba National Park, Rio de Ja- neiro State, Brazil trough the analysis of fecal samples collected in two seasons of the year. During a period of four years, 28 fecal samples of Cerdocyon thous were collected in different parts of Restinga de Jurubatiba, being 19 out of them from dry season and nine from rainy season. In each season and between seasons, data analysis showed that inver- tebrates, vertebrates and fruits consumption did not signifi cantly differ. Among vertebrates, mammals were the most eaten item (50%) in relation to reptiles (43%) and birds (32%). The rice-rat, Cerradomys subfl avus, and the collared-lizard, Tropidurus torquatus, were mainly eaten during the rainy season, whereas birds, during the dry season. Furthermore, the only item identifi ed that differed among seasons was the lizard Tropidurus torquatus that appeared in 77.8% of samples derived from the rainy season and 21.0%, in those from the dry season, with a total frequency of 39.3%. In relation to seed dispersion, fi ve species found in lees were identifi ed and their viabilities were evaluated through germi- nation tests in Petri dishes. Excepting for Brazilian cherry (pitanga), Eugenia umbellifl ora, from which 56% of the seeds germinated, no other seed species consumed have germi- nated after passing through the C. thous digestive tract.